While soldering in many instances is a satisfactory method of making electrical connections, alternatives have been proposed as motivated, e.g., by a desire to simplify large-scale commercial practice. For example,
U.S. Pat. No. 4,065,197, issued Dec. 27, 1977 to C. H. Kuist et al.,
U.S. Pat. No. 4,118,102, issued Oct. 3, 1978 to C. H. Kuist et al., and the paper by
C. H. Kuist, Anisotropic Conduction in Elastomeric Composites, Electronic Connector Study Group Inc., Seventh Annual Connector Symposium Proceedings, 1974, pp. 204-210
disclose an electrical connector in sheet form which is made from a mixture of flexible insulator material and metal particles, the sheet having relatively low electrical resistance between closely spaced points which typically are on opposing surfaces, and the sheet having relatively high resistance between any two points spaced beyond a critical isolation distance.
Common to the cited references is randomization of conductive particles in a nonconductive matrix material, this in contrast to alignment of such particles as disclosed in
Japanese Patent Application Publication 55-152033, "Anisotropically Conductive Rubber Sheet", published Sept. 9, 1983 by K. Arai et al. and
Japanese Patent Application Publication 55-159578, "Connector", published May 30, 1979 by K. Arai et al.